Mobile spar

ABSTRACT

A boom support and raising and lowering mechanism for pivoting the boom to swing in a generally vertical plane to raise and lower the same which includes a boom pivotally mounted on a saddle-type support for straddling a vehicle and being detachably connectable to the same. The raising and lowering mechanism consists of a power actuated articulated link assembly including a first rigid member pivotally connected at one end to the boom support and at the opposite end to an hydraulic extendible and retractable cylinder pivotally connected to the boom approximately mid-length thereof. A further support is provided supporting the rigid link member in a generally horizontal position at which position the hydraulic cylinder effects raising and lowering of the boom and supports the boom in a horizontal travel position. Four guy lines are provided, two of which remain connected during raising and lowering of the boom for stabilizing the same, the third one of which becomes taut when the boom is raised to a vertical position and at which time the fourth stay is connected to the support.

Hurley Mar. 11, 1975 1 1 MOBILE SPAR [75] Inventor: Murray E. Burley, Nanaimo, British Columbia, Canada [73] Assignee: S. Madill Ltd., Nanaimo, British Columbia, Canada 22 Filed: May 3,1974

21 Appl. No.: 466,831

[30] Foreign Application Priority Data Apr. 18, 1973 Canada 169111 [52] U.S. C1. 212/8 R, 52/116, 214/130 R [51] Int. Cl. B660 23/00 [58] Field of Search 9/39; 212/8 R, 8 A, 8 B,

212/35 R, 58 R, 58 A; 240/67; 214/851,

85.5,130 R, 778, 131 R, 131 A; 52/116, 117,1l8,l19,l20, 121,122,123

I Primary Examiner-Robert J) Spar Assistant ExaminerLawrence J. Oresky Attorney, Agent, or Firm-Stanley E. Johnson [5 7] 5 ABSTRACT A boom support and raising and lowering mechanism for pivoting the boom to swing in a generally vertical plane to raise and lower the same which includes a boom pivotally mounted on a saddle-type support for straddling a vehicle and being detachably connectable to the same. The raising and lowering mechanism consists of a power actuated articulated link assembly including a first rigid member pivotally connected at one end to the boom support and at the opposite end to an hydraulic extendible and retractable cylinder pivotally connected to the boom approximately midlength thereof. A further support is provided supporting the rigid link member in a generally horizontal position at which position the hydraulic cylinder effects raising and lowering of the boom and supports the boom in a horizontal travel position. Four g uy lines are provided, two of which remain connected during raising and lowering of the boom for stabilizing the same, the third one of which becomes taut when the boom is raised to a vertical position and at which time the fourth stay is connected to the support.

6 Claims, 4 Drawing Figures MOBILE SPAR FIELD OF INVENTION This invention relates to a novel mounting arrangement for a boom on a vehicle and particularly to yarding machines used in small timber wherein a spar tree is mounted on a mobile vehicle and designed to travel with the spar elevated to a vertical yarding position or lowered to a horizontal position.

DESCRIPTION OF PRIOR ART Mobile spar trees are known, one of which is disclosed in Canadian Pat. No. 692,363, issued Aug. 11, 1964 to The Humboldt Company. In the patented structure a spar tree is pivotally mounted on a support on the vehicle and is raised from a horizontal to a vertical position by an hydraulic cylinder and is lowered by the same from the vertical to a horizontal position. In a horizontal position the boom is supported mid-way of its length on a further support on the vehicle. A similar arrangement is disclosed in Canadian Pat. No. 730,522, issued Mar. 22, 1966 to the Weyerhaeuser Company. A portable spar tree incorporating a further different raising and lowering mechanism is disclosed in Canadian Pat. No. 788,305, issued June 25, 1968 to The Humboldt Company. In each instance of the patented structures the raising and lowering mechanism is in a fixed location closely adjacent the boom and pivotal mounting of the same to the vehicle on which it is mounted.

A principal object of the present invention is to provide improvements in the raising and lowering mechanismlwhich permits moving the power actuating device to an effective boom raising position and thereafter moving the same closely adjacent the boom when the latter is in a vertical position.

A further principal object of the present invention is to provide in combination with the raising and lowering mechanism guy support lines which are attached respectively at opposite ends to thevehicle and the boom and at further positions such as to stabilize the boom during the raising and lowering operation.

In the present arrangement a power actuated articulated link means is used for pivoting the boom from one ofa horizontal and a vertical position to the other to effect raising and lowering of the boom. Power actuated link means for such purpose is known as exemplified by Canadian Pat. No. 637,922, issued Mar. 6, 1962 to Herman J. Troche, et al., assignors to Holan Corporation. In the patented arrangement the power actuated link mechanism is utilized for only raising and lowering of the boom.

It is an object of the present invention to provide an arrangement whereby the raising and lowering mechanism is utilized to effect raising and lowering of the boom and further provide a support for the boom when the boom is in its horizontal position.

SUMMARY OF INVENTION Accordingly there is provided in accordance with the present invention in a boom pivotally mounted on a mobile support for swinging movement in a generally vertical plane to raise and lower the same, a first support means, means pivotally mounting one end of the boom on said support, power actuated articulated means for pivoting the boom from one of a horizontal position and a vertical position to the other to raise and lower said boom, said link means comprising a rigid link member pivotally connected at one end thereof to said first support adjacent the pivotal connection of the boom thereto and a power actuated extendible retractable member pivotally connected at one end to the other end of said rigid link member and at the opposite end to said boom, said latter pivotal connection being spaced from the pivotal connection of the boom to said first support and a second support spaced horizontally from said first support and located at a position to support said first rigid link member in a generally horizontal position. The second support is disposed below the boom in a boom horizontal position and a pair of guy lines are connected at one end to the boom and at the opposite end to said first support respectively on opposite sides of said vertical plane. The pair of guy lines are arranged to remain taut stabilizing said boom during the raising and lowering of the same.

DESCRIPTION OF DRAWINGS The invention is illustrated by way of example in the accompanying drawings wherein:

FIG. 1 is a side elevational view showing the boom a horizontal lowered position;

FIG. 2 is a side elevational view similar to FIG. 1 showing the boom in a vertical raised position;

FIG. 3 is a side elevational view showing the boom in a vertical raised operative position; and

FIG. 4 is a front elevational view of the raised boom shown in FIG. 3.

DETAILED DESCRIPTION or PREFERRED EMBODIMENT Referring now in detail to the drawings shown in FIG. 1 is a mobile crawler type vehicle 10 having a boom 20 pivotally supported thereon by a support 30 detachably connected to the vehicle. The boom is raised from its horizontal position, shown in FIG. 1, to the vertical position, shown in FIGS. 2, 3 and 4, by a power actuated articulated link means 40. The latter is supported by a second support 50 secured to the tractor at a position forwardly of the first support 30. The boom is stabilized during raising and lowering by a pair of guy lines 60 and 61. As the boom is raised to its vertical position a guy line 62 becomes taut and a four guy line 63 is then attached to the vehicle providing a four point guy support for the raised boom.

The tractor unit 10 may be of any conventional crawler or wheel type vehicle and is straddled by the first boom support 30. The first boom support 30 is of a saddle type having an upper boom supporting portion 31 to which the boom is pivotally connected by pivot pin 21 and a pair of downwardly projecting legs 32 and 33 located respectively on opposite sides of the vehicle and detachably connected thereto by removable pins 34. A pair of guy anchors 35 and 36 are secured to the support 30 respectively on opposite sides of the vehicle terminating at upper ends whereat respective guy lines 60 and 61 are attached substantially on the pivot axis of pivot pin 21.

The power actuated articulated link boom raising mechanism 40 consists of a first rigid member 41 and a dual stage double acting hydraulic cylinder 42 pivotally interconnected by a pin 43. The rigid link member 41 is pivotally connected to the first support 30 by a pivot pin 44 located closely adjacent the boom pivot mounting pin 21. The hydraulic cylinder 42 is pivotally 3 connected to the boom 20 by a pivot pin 45 at a position approximately mid-length of the boom.

The second support 50 is mounted on the tractor so as to be located vertically below the boom in a boom horizontal position and supports the rigid boom member 41 closely adjacent its pivotal connection to the hydraulic cylinder. The second support 50 accordingly provides a reaction point for the hydraulic cylinder during raising of the boom.

The boom, as will be seen from FIG. 4, is canted to one side from a vertical plane. For the purpose however of discussion herein the boom is described as being swingable in a generally vertical plane in its pivotal movement about pivot pin 21 during raising and lowering of the boom. The guy lines 60 and 61 are connected to respective anchors 35 and 36 at a position substantially on the pivot axis of the boom pivot mounting pin 21, such guy lines accordingly remain taut during raising and lowering of the boom thus stabilizing thesame. Once the boom is pivoted to its full vertical position the third guy 62 is drawn taut and the fourth guy 64 is then fixed to the tractor, guys 60, 61, 62 and 63 thereby providing a four point support for the boom or spar tree 20. After the boom has been stayed in its vertical position the hydraulic cylinder 42 is retracted pivoting the rigid member 41 to a position generally parallel to the boom as illustrated in FIG. 3. To lower the boom the cylinder 42 is extended until the leg member 41 comes to rest on the support 50. The guy line 62 is then disconnected and the cylinder pulls the spar tree off the vertical position and controls the descent of the spar tree to the horizontal position. In the horizontal position the collapsed hydraulic cylinder42 becomes a brace and firmly supports the boom or spar tree in the horizontal position. The boom in its horizontal position projects longitudinally of the vehicle and fowardly therefrom. The hydraulic cylinder 42 by contact with the support 50 and its connection to the boom at the length of the boom provides a relatively stable support for the boom on the vehicle. The stability of the machine is such that it can travel with the spar tree lowered and by utilizing the guy lines in the boom raised position the stability is also such that the machine can travel with the boom in its raised position. i

The mobile spar tree is provided with sheaves 70 on the upper end thereof for guiding cables in a cable winch system controlled by a power driven winch 80 mounted on the support assembly 30.

From the foregoing, it will be self-evident there is provided a mobile yarding machine which can readily travel under its own power with the boom either raised or lowered. In the lowered position, the entire machine can readily travel through openings of approximately 12 X 12 feet without dismantling parts of the raising and lowering mechanism or removing the boom.

I claim:

1. In a boom pivotally mounted on a support for swinging movement in a generally vertical plane to raise and lower the same:

a. a first support;

b. means pivotally mounting one end of said boom on said support;

c. power actauted articulated link means for pivoting the boom from one of a horizontal position and a vertical position to the other to raise and lower said boom, said link means comprising:

1. a rigid link member freely pivotally connected at one end to said first support adjacent the pivotal connection of the boom; and

2. a power actuated extendible and retractable member pivotally connected at one end to the other end of said rigid link member and at the opposite end to said boom, said latter pivotal connection being spaced from the pivotal connection of the boom to said first support;

d. a second support spaced horizontally from said first support upon which said first rigid link member detachably rests when in a generally horizontal position, said second support being disposed below the boom in a boom horizontal position, and

e. a winch mechanism mounted on'said first support and including a cable, said cable being operatively associated with said winch and said boom for hauling in a load connected to the cable.

2. The apparatus of claim 1 including a pair of guy lines connected at one end to said boom and at the opposite end to said first support respectively on opposite sides of said vertical plane, said guy lines stabilizing said boom during raising and lowering of the same.

3. The apparatus of claim 1 wherein said first support comprises a saddle type support having an upper boom supporting portion and legs projecting downwardly therefrom for straddling a mobile vehicle and means for detachably connecting the same to such vehicle.

4. Apparatus as defined in claim 3 wherein said pair of guy lines are connected to said support substantially on the pivotal axis of said boom.

5. Apparatus as defined in claim 1 wherein said extendible and retractable power actuated member comprises an hydraulic cylinder.

6. Apparatus as defined in claim 1 wherein the spacing of the pivotal connections of the boom and rigid link member to the support is such that the link member and power actuated member are parallel to and closely adjacent the boom in a boom raised position. 

1. a rigid link member freely pivotally connected at one end to said first support adjacent the pivotal connection of the boom; and
 1. In a boom pivotally mounted on a support for swinging movement in a generally vertical plane to raise and lower the same: a. a first support; b. means pivotally mounting one end of said boom on said support; c. power actauted articulated link means for pivoting the boom from one of a horizontal position and a vertical position to the other to raise and lower said boom, said link means comprising:
 1. In a boom pivotally mounted on a support for swinging movement in a generally vertical plane to raise and lower the same: a. a first support; b. means pivotally mounting one end of said boom on said support; c. power actauted articulated link means for pivoting the boom from one of a horizontal position and a vertical position to the other to raise and lower said boom, said link means comprising:
 1. a rigid link member freely pivotally connected at one end to said first support adjacent the pivotal connection of the boom; and
 2. a power actuated extendible and retractable member pivotally connected at one end to the other end of said rigid link member and at the opposite end to said boom, said latter pivotal connection being spaced from the pivOtal connection of the boom to said first support; d. a second support spaced horizontally from said first support upon which said first rigid link member detachably rests when in a generally horizontal position, said second support being disposed below the boom in a boom horizontal position, and e. a winch mechanism mounted on said first support and including a cable, said cable being operatively associated with said winch and said boom for hauling in a load connected to the cable.
 2. The apparatus of claim 1 including a pair of guy lines connected at one end to said boom and at the opposite end to said first support respectively on opposite sides of said vertical plane, said guy lines stabilizing said boom during raising and lowering of the same.
 2. a power actuated extendible and retractable member pivotally connected at one end to the other end of said rigid link member and at the opposite end to said boom, said latter pivotal connection being spaced from the pivOtal connection of the boom to said first support; d. a second support spaced horizontally from said first support upon which said first rigid link member detachably rests when in a generally horizontal position, said second support being disposed below the boom in a boom horizontal position, and e. a winch mechanism mounted on said first support and including a cable, said cable being operatively associated with said winch and said boom for hauling in a load connected to the cable.
 3. The apparatus of claim 1 wherein said first support comprises a saddle type support having an upper boom supporting portion and legs projecting downwardly therefrom for straddling a mobile vehicle and means for detachably connecting the same to such vehicle.
 4. Apparatus as defined in claim 3 wherein said pair of guy lines are connected to said support substantially on the pivotal axis of said boom.
 5. Apparatus as defined in claim 1 wherein said extendible and retractable power actuated member comprises an hydraulic cylinder. 